My first Orange Amp - cant even get it open

[spydox]

This is an Orange Crush 20L amp. This amp blows fuses within 1/2 second of installing a new one. Just before, it has a brief 60Hz hum. I suspect power supply - specifically rectifier. I'd like to get into it and start probing but that's the issue; I can't get the chassis out.



I removed the 4 screws circled in blue and removed the carrying handle. The WHITE chassis won't come out- it seems like something is holding it on top but I don't see any other screws. I tried to gently pull it towards the back to slide it out but it seems to he held fast.

As far as the RED circled screws that's even more of a mystery because after removing them, I can't get the orange panel they are in loose at all. It seems like its glued in which makes me wonder why the screws are even there?

But if I can get the chassis loose that should be all I need. I can pry it back slightly and can tell its loose on the back- only stuck at the top.

Thanks in advance for advice. It's a very clean looking amp so I didn't wanna get too aggressive with removing any of the hardware..

S 

[DrGonz78]

It's all about being aggressive and very careful all at the same time. Many times you'll get the sucker out, but yeah it will leave some markings. Work on getting the orange back board out first... Then you can get your hands on other parts of the chassis to wiggle it free. I some times use a flat wood tool or something to lightly separate the stuck parts as I wiggle. It's fun stuff!!  :trouble

[Roly]

Apart from being very tight; the top four screws (and some others) may well hold the amp chassis to the back plate.

Cabinet makers and chassis builders seem to live by different measurement tolerances.

[J M Fahey]

The WHITE chassis won't come out- it seems like something is holding it on top but I don't see any other screws.

Try the handle 

[tonyharker]

Looking here http://talk.philmusic.com/index.php?topic=116207.0 it doesn't appear to be the handle.

[Enzo]

First I suspect your diagnosis is wrong, my first suspects would be bad output device as way more likely.

Nothing is glued together there, but the tolex is probably stuck.   With screws out, then pry the lower wood panel off.   The vinyl tolex surfaces are probably sticking together.   Once that board is off, then it sould be easier to free the chassis, which is also probably stuck to the cab tolex.

[joecool85]

I've not worked on an Orange amp, but have taken apart others with similar build style/quality.  One I actually had to shave down the metal chassis to get it back into the wooden cabinet without doing any damage to the tolex...what a pain.

[J M Fahey]

Why make things the hard way?

You just need this simple tool:


  :duh  :lmao:

[Roly]

You have it far too easy JM.

First I suspect your diagnosis is wrong, my first suspects would be bad output device as way more likely.

Yup.  Boofed output transistor or chip amp by the sound of the sound of it.   :dbtu:



Do you need a hand getting that open @spydox?

8|


{edit to remove comment intended for another thread}

[Bajaguy]

On many of the smaller practice amplifiers the handle screws are attached to the chassis, so removal of the handle is required to remove the cabinet. It is very common that the tolex is so tight that the metal chassis will have to be gently persuaded out. Be very carefull, Tolex can be a bear to repair/replace if you mess it up.

Usually the 60Hz tone is a big sign that the output device is toast. The last amp I fixed that showed that fault was outputing almost 40 volts DC to the speaker, so make sure that the speaker is unharmed before you put it all back together.

You have some great advice from some of the best techs availible on the net, so be sure to follow thier advice and you'll be well on your way to a working amplifier.

Best of luck,

Baja

[DIYmastermind]

Okay i think i may have a bit of input. i own a orange ppc108 cab, and have tried fooling around with speaker swaps, so i know how difficult they can be to get open. the tolex sticks to itself very well. so when you take the screws out and can't get the back panel out, most likely the tolex is sticking to itself making you think it's glued in place. when in reality, all you need is a putty knife and a bit of patience. simply pry it out, being careful not to tear or cut the tolex. regardless though, if a cab is hard to get apart that's quality craftsmanship. . . IMO.

[DrGonz78]

I am still wondering if the guy ever got his cover off?  :lmao:

[DIYmastermind]

I am still wondering if the guy ever got his cover off?  :lmao:

Haha i'm pondering the same query too, gonz

[Roly]

Me too.  First and last post on the same day in October, hit and run, so I think this may remain one of life's little mysteries.

Or maybe he's still struggling.   :lmao:

[thehallofshields]

I can bring some close to this thread.

I had the same problem. Turns out you have to remove the handle.

Thanks J M Fahey.